Merge pull request #97 from sunfishcode/sunfishcode/update-wasi-sockets

Update to the latest wasi-sockets.

Author: Mossaka

wit/deps.lock

@@ -25,5 +25,5 @@ sha512 = "cc4fa3d178559a89d9d6a376e3359b892158d1e73317c5db1f797ebc6b0b57abf24227
 
 [sockets]
 url = "https://github.com/WebAssembly/wasi-sockets/archive/main.tar.gz"
-sha256 = "40863017f355ac90c57630cc00b94518804e8e2c5694a7870b7a54dbdcda0e08"
-sha512 = "2d6a919247430e869bf85a06a6a1d198f04368951e76c1fec7961b2b07af381c58c8e8b9079c91925dfbf80976971213329be57d59a90bae6e4e6460b073dc88"
+sha256 = "9a3816bfa5a8b0673e5651024d8f9a1540f169f6d70f2bde6ee0e8240cd177ee"
+sha512 = "bfcce89127510e16e9e7d7ac058ba3108953067e2d53f05cb1020dadf552738753b7fc9d10797236f2ced089063de7ac853fd9526079758fab1419d9b58a5212"

wit/deps/sockets/tcp.wit

@@ -15,25 +15,45 @@ interface tcp {
         /// Similar to `SHUT_RDWR` in POSIX.
         both,
     }
-
-
-    /// A TCP socket handle.
+    
+    /// A TCP socket resource.
+    ///
+    /// The socket can be in one of the following states:
+    /// - `unbound`
+    /// - `bind-in-progress`
+    /// - `bound` (See note below)
+    /// - `listen-in-progress`
+    /// - `listening`
+    /// - `connect-in-progress`
+    /// - `connected`
+    /// - `closed`
+    /// See <https://github.com/WebAssembly/wasi-sockets/TcpSocketOperationalSemantics.md>
+    /// for a more information.
+    ///
+    /// Note: Except where explicitly mentioned, whenever this documentation uses
+    /// the term "bound" without backticks it actually means: in the `bound` state *or higher*.
+    /// (i.e. `bound`, `listen-in-progress`, `listening`, `connect-in-progress` or `connected`)
+    ///
+    /// In addition to the general error codes documented on the
+    /// `network::error-code` type, TCP socket methods may always return
+    /// `error(invalid-state)` when in the `closed` state.
     resource tcp-socket {
         /// Bind the socket to a specific network on the provided IP address and port.
         ///
         /// If the IP address is zero (`0.0.0.0` in IPv4, `::` in IPv6), it is left to the implementation to decide which
         /// network interface(s) to bind to.
         /// If the TCP/UDP port is zero, the socket will be bound to a random free port.
         ///
-        /// Unlike in POSIX, this function is async. This enables interactive WASI hosts to inject permission prompts.
+        /// Bind can be attempted multiple times on the same socket, even with
+        /// different arguments on each iteration. But never concurrently and
+        /// only as long as the previous bind failed. Once a bind succeeds, the
+        /// binding can't be changed anymore.
         ///
-        /// # Typical `start` errors
+        /// # Typical errors
         /// - `invalid-argument`:          The `local-address` has the wrong address family. (EAFNOSUPPORT, EFAULT on Windows)
         /// - `invalid-argument`:          `local-address` is not a unicast address. (EINVAL)
         /// - `invalid-argument`:          `local-address` is an IPv4-mapped IPv6 address. (EINVAL)
         /// - `invalid-state`:             The socket is already bound. (EINVAL)
-        ///
-        /// # Typical `finish` errors
         /// - `address-in-use`:            No ephemeral ports available. (EADDRINUSE, ENOBUFS on Windows)
         /// - `address-in-use`:            Address is already in use. (EADDRINUSE)
         /// - `address-not-bindable`:      `local-address` is not an address that the `network` can bind to. (EADDRNOTAVAIL)
@@ -46,6 +66,11 @@ interface tcp {
         /// socket option should be set implicitly on all platforms, except on Windows where this is the default behavior
         /// and SO_REUSEADDR performs something different entirely.
         ///
+        /// Unlike in POSIX, in WASI the bind operation is async. This enables
+        /// interactive WASI hosts to inject permission prompts. Runtimes that
+        /// don't want to make use of this ability can simply call the native
+        /// `bind` as part of either `start-bind` or `finish-bind`.
+        ///
         /// # References
         /// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/bind.html>
         /// - <https://man7.org/linux/man-pages/man2/bind.2.html>
@@ -57,32 +82,40 @@ interface tcp {
         /// Connect to a remote endpoint.
         ///
         /// On success:
-        /// - the socket is transitioned into the Connection state
+        /// - the socket is transitioned into the `connection` state.
         /// - a pair of streams is returned that can be used to read & write to the connection
         ///
-        /// After a failed connection attempt, the only valid action left is to
-        /// `drop` the socket. A single socket can not be used to connect more than once.
+        /// After a failed connection attempt, the socket will be in the `closed`
+        /// state and the only valid action left is to `drop` the socket. A single
+        /// socket can not be used to connect more than once.
         ///
-        /// # Typical `start` errors
+        /// # Typical errors
         /// - `invalid-argument`:          The `remote-address` has the wrong address family. (EAFNOSUPPORT)
         /// - `invalid-argument`:          `remote-address` is not a unicast address. (EINVAL, ENETUNREACH on Linux, EAFNOSUPPORT on MacOS)
         /// - `invalid-argument`:          `remote-address` is an IPv4-mapped IPv6 address. (EINVAL, EADDRNOTAVAIL on Illumos)
         /// - `invalid-argument`:          The IP address in `remote-address` is set to INADDR_ANY (`0.0.0.0` / `::`). (EADDRNOTAVAIL on Windows)
         /// - `invalid-argument`:          The port in `remote-address` is set to 0. (EADDRNOTAVAIL on Windows)
         /// - `invalid-argument`:          The socket is already attached to a different network. The `network` passed to `connect` must be identical to the one passed to `bind`.
-        /// - `invalid-state`:             The socket is already in the Connection state. (EISCONN)
-        /// - `invalid-state`:             The socket is already in the Listener state. (EOPNOTSUPP, EINVAL on Windows)
-        ///
-        /// # Typical `finish` errors
+        /// - `invalid-state`:             The socket is already in the `connected` state. (EISCONN)
+        /// - `invalid-state`:             The socket is already in the `listening` state. (EOPNOTSUPP, EINVAL on Windows)
         /// - `timeout`:                   Connection timed out. (ETIMEDOUT)
         /// - `connection-refused`:        The connection was forcefully rejected. (ECONNREFUSED)
         /// - `connection-reset`:          The connection was reset. (ECONNRESET)
         /// - `connection-aborted`:        The connection was aborted. (ECONNABORTED)
         /// - `remote-unreachable`:        The remote address is not reachable. (EHOSTUNREACH, EHOSTDOWN, ENETUNREACH, ENETDOWN, ENONET)
         /// - `address-in-use`:            Tried to perform an implicit bind, but there were no ephemeral ports available. (EADDRINUSE, EADDRNOTAVAIL on Linux, EAGAIN on BSD)
-        /// - `not-in-progress`:           A `connect` operation is not in progress.
+        /// - `not-in-progress`:           A connect operation is not in progress.
         /// - `would-block`:               Can't finish the operation, it is still in progress. (EWOULDBLOCK, EAGAIN)
         ///
+        /// # Implementors note
+        /// The POSIX equivalent of `start-connect` is the regular `connect` syscall.
+        /// Because all WASI sockets are non-blocking this is expected to return
+        /// EINPROGRESS, which should be translated to `ok()` in WASI.
+        ///
+        /// The POSIX equivalent of `finish-connect` is a `poll` for event `POLLOUT`
+        /// with a timeout of 0 on the socket descriptor. Followed by a check for
+        /// the `SO_ERROR` socket option, in case the poll signaled readiness.
+        ///
         /// # References
         /// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/connect.html>
         /// - <https://man7.org/linux/man-pages/man2/connect.2.html>
@@ -93,22 +126,24 @@ interface tcp {
 
         /// Start listening for new connections.
         ///
-        /// Transitions the socket into the Listener state.
+        /// Transitions the socket into the `listening` state.
         ///
-        /// Unlike POSIX:
-        /// - this function is async. This enables interactive WASI hosts to inject permission prompts.
-        /// - the socket must already be explicitly bound.
+        /// Unlike POSIX, the socket must already be explicitly bound.
         ///
-        /// # Typical `start` errors
+        /// # Typical errors
         /// - `invalid-state`:             The socket is not bound to any local address. (EDESTADDRREQ)
-        /// - `invalid-state`:             The socket is already in the Connection state. (EISCONN, EINVAL on BSD)
-        /// - `invalid-state`:             The socket is already in the Listener state.
-        ///
-        /// # Typical `finish` errors
+        /// - `invalid-state`:             The socket is already in the `connected` state. (EISCONN, EINVAL on BSD)
+        /// - `invalid-state`:             The socket is already in the `listening` state.
         /// - `address-in-use`:            Tried to perform an implicit bind, but there were no ephemeral ports available. (EADDRINUSE)
-        /// - `not-in-progress`:           A `listen` operation is not in progress.
+        /// - `not-in-progress`:           A listen operation is not in progress.
         /// - `would-block`:               Can't finish the operation, it is still in progress. (EWOULDBLOCK, EAGAIN)
         ///
+        /// # Implementors note
+        /// Unlike in POSIX, in WASI the listen operation is async. This enables
+        /// interactive WASI hosts to inject permission prompts. Runtimes that
+        /// don't want to make use of this ability can simply call the native
+        /// `listen` as part of either `start-listen` or `finish-listen`.
+        ///
         /// # References
         /// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/listen.html>
         /// - <https://man7.org/linux/man-pages/man2/listen.2.html>
@@ -119,7 +154,7 @@ interface tcp {
 
         /// Accept a new client socket.
         ///
-        /// The returned socket is bound and in the Connection state. The following properties are inherited from the listener socket:
+        /// The returned socket is bound and in the `connected` state. The following properties are inherited from the listener socket:
         /// - `address-family`
         /// - `keep-alive-enabled`
         /// - `keep-alive-idle-time`
@@ -133,7 +168,7 @@ interface tcp {
         /// a pair of streams that can be used to read & write to the connection.
         ///
         /// # Typical errors
-        /// - `invalid-state`:      Socket is not in the Listener state. (EINVAL)
+        /// - `invalid-state`:      Socket is not in the `listening` state. (EINVAL)
         /// - `would-block`:        No pending connections at the moment. (EWOULDBLOCK, EAGAIN)
         /// - `connection-aborted`: An incoming connection was pending, but was terminated by the client before this listener could accept it. (ECONNABORTED)
         /// - `new-socket-limit`:   The new socket resource could not be created because of a system limit. (EMFILE, ENFILE)
@@ -175,7 +210,7 @@ interface tcp {
         /// - <https://man.freebsd.org/cgi/man.cgi?query=getpeername&sektion=2&n=1>
         remote-address: func() -> result<ip-socket-address, error-code>;
 
-        /// Whether the socket is listening for new connections.
+        /// Whether the socket is in the `listening` state.
         ///
         /// Equivalent to the SO_ACCEPTCONN socket option.
         is-listening: func() -> bool;
@@ -193,7 +228,7 @@ interface tcp {
         /// # Typical errors
         /// - `not-supported`:        (set) The platform does not support changing the backlog size after the initial listen.
         /// - `invalid-argument`:     (set) The provided value was 0.
-        /// - `invalid-state`:        (set) The socket is already in the Connection state.
+        /// - `invalid-state`:        (set) The socket is in the `connect-in-progress` or `connected` state.
         set-listen-backlog-size: func(value: u64) -> result<_, error-code>;
 
         /// Enables or disables keepalive.
@@ -253,8 +288,6 @@ interface tcp {
         ///
         /// # Typical errors
         /// - `invalid-argument`:     (set) The TTL value must be 1 or higher.
-        /// - `invalid-state`:        (set) The socket is already in the Connection state.
-        /// - `invalid-state`:        (set) The socket is already in the Listener state.
         hop-limit: func() -> result<u8, error-code>;
         set-hop-limit: func(value: u8) -> result<_, error-code>;
 
@@ -268,14 +301,25 @@ interface tcp {
         ///
         /// # Typical errors
         /// - `invalid-argument`:     (set) The provided value was 0.
-        /// - `invalid-state`:        (set) The socket is already in the Connection state.
-        /// - `invalid-state`:        (set) The socket is already in the Listener state.
         receive-buffer-size: func() -> result<u64, error-code>;
         set-receive-buffer-size: func(value: u64) -> result<_, error-code>;
         send-buffer-size: func() -> result<u64, error-code>;
         set-send-buffer-size: func(value: u64) -> result<_, error-code>;
 
-        /// Create a `pollable` which will resolve once the socket is ready for I/O.
+        /// Create a `pollable` which can be used to poll for, or block on,
+        /// completion of any of the asynchronous operations of this socket.
+        ///
+        /// When `finish-bind`, `finish-listen`, `finish-connect` or `accept`
+        /// return `error(would-block)`, this pollable can be used to wait for
+        /// their success or failure, after which the method can be retried.
+        ///
+        /// The pollable is not limited to the async operation that happens to be
+        /// in progress at the time of calling `subscribe` (if any). Theoretically,
+        /// `subscribe` only has to be called once per socket and can then be
+        /// (re)used for the remainder of the socket's lifetime.
+        ///
+        /// See <https://github.com/WebAssembly/wasi-sockets/TcpSocketOperationalSemantics.md#Pollable-readiness>
+        /// for a more information.
         ///
         /// Note: this function is here for WASI Preview2 only.
         /// It's planned to be removed when `future` is natively supported in Preview3.
@@ -297,7 +341,7 @@ interface tcp {
         /// The shutdown function does not close (drop) the socket.
         ///
         /// # Typical errors
-        /// - `invalid-state`: The socket is not in the Connection state. (ENOTCONN)
+        /// - `invalid-state`: The socket is not in the `connected` state. (ENOTCONN)
         ///
         /// # References
         /// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/shutdown.html>

wit/deps/sockets/udp.wit

@@ -43,19 +43,21 @@ interface udp {
         /// network interface(s) to bind to.
         /// If the port is zero, the socket will be bound to a random free port.
         ///
-        /// Unlike in POSIX, this function is async. This enables interactive WASI hosts to inject permission prompts.
-        ///
-        /// # Typical `start` errors
+        /// # Typical errors
         /// - `invalid-argument`:          The `local-address` has the wrong address family. (EAFNOSUPPORT, EFAULT on Windows)
         /// - `invalid-state`:             The socket is already bound. (EINVAL)
-        ///
-        /// # Typical `finish` errors
         /// - `address-in-use`:            No ephemeral ports available. (EADDRINUSE, ENOBUFS on Windows)
         /// - `address-in-use`:            Address is already in use. (EADDRINUSE)
         /// - `address-not-bindable`:      `local-address` is not an address that the `network` can bind to. (EADDRNOTAVAIL)
         /// - `not-in-progress`:           A `bind` operation is not in progress.
         /// - `would-block`:               Can't finish the operation, it is still in progress. (EWOULDBLOCK, EAGAIN)
         ///
+        /// # Implementors note
+        /// Unlike in POSIX, in WASI the bind operation is async. This enables
+        /// interactive WASI hosts to inject permission prompts. Runtimes that
+        /// don't want to make use of this ability can simply call the native
+        /// `bind` as part of either `start-bind` or `finish-bind`.
+        ///
         /// # References
         /// - <https://pubs.opengroup.org/onlinepubs/9699919799/functions/bind.html>
         /// - <https://man7.org/linux/man-pages/man2/bind.2.html>